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HPA (High Pressure Aeroponics)

Posted by ethnobotany (My Page) on
Tue, Nov 20, 12 at 0:07

So there are a few things I need to know.

First off, I need to know how many sprayheads I would need for my system. Right now I have 4X 3' gullies made from 4'' x 4'' PVC fence posts. Each fence post has 3 netty cups separated by approximately 8''.

Would 4 nozzles in each gully be overkill?

I plan on using the following items:

PUMP: Aquatec 6800 SET-68
- operates at 80 psi with 0.38LPM
- inlet and outlet 1/4'' quick connectors

TRANSFORMER: 24V to 110V transformer

PRESSURE GAUGE

SOLENOID VALVE W/ 1/4'' QUICK CONNECTORS

PRESSURE SWITCH
- this is factory set to turn the pump on when pressure falls below 40 psi, and to turn off when the pressure rises above 55 psi.
- it can be adjusted +/- 5 psi for both values

FOGGER MISTERS
- these have a 0.8 GPH rating
- 35 to 80 psi rating
- droplet size of 60 to 100 micron
- cleanable

ACCUMULATOR TANK
- Amtrol WX-101 (140PR1) Well-X-Trol In-Line Well Water Tank, 2 Gal.

CYCLE TIMER
- CAP-ART DNe Adjustable Recycling Timer
- down to 1 second intervals

This post was edited by ethnobotany on Tue, Mar 19, 13 at 1:29

So there are a few things I need to know.

First off, I need to know how many sprayheads I would need for my system. Right now I have 4X 3' gullies made from 4'' x 4'' PVC fence posts. Each fence post has 3 netty cups separated by approximately 8''.

Would 4 nozzles in each gully be overkill?

I plan on using the following items:

PUMP: Aquatec 6800 SET-68
- operates at 80 psi with 0.38LPM
- inlet and outlet 1/4'' quick connectors

TRANSFORMER: 24V to 110V transformer

PRESSURE GAUGE

SOLENOID VALVE W/ 1/4'' QUICK CONNECTORS

PRESSURE SWITCH
- this is factory set to turn the pump on when pressure falls below 40 psi, and to turn off when the pressure rises above 55 psi.
- it can be adjusted +/- 5 psi for both values

FOGGER MISTERS
- these have a 0.8 GPH rating
- 35 to 80 psi rating
- droplet size of 60 to 100 micron
- cleanable

ACCUMULATOR TANK
** still looking, suggestions welcome!

CYCLE TIMER
** also still looking for this!


Follow-Up Postings:

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RE: HPA (High Pressure Aeroponics)

Ethno
Here is a link to a site showing how to build a simple cycle timer. I haven't built it myself but got the link from Hex a year or two ago. be aware you have to register to see the images and the site deals with growing alternative medicinal plants. BUT, the information is very useful.
Hope this helps you.


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RE: HPA (High Pressure Aeroponics)

4 nozzles in a 3' rail isn't overkill. You could have a few more. The neat part of aeroponics is that you can put them anywhere, like the sides or top. Just try to make it so that you can reach them to unscrew and unclog them.

If your misters are like the ones I've seen, the right socket and extension makes an easy little wrench to screw and unscrew the mister heads. When you build the system, you drill and then run a tap through the hole to make threaded holes in the pvc. The mister head screws into that. But I imagine there are other ways to do it, too.

Cycle timers are about a hundred bucks. wormsway.com sells them. It would be ideal to buy one from a local store, so you can take it back and exchange it if it breaks. You'll want a spare as well. I haven't used all of that equipment you listed, but especially with anything electronic - you want a backup. Aero systems are not very forgiving when something breaks and the system stops working.


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RE: HPA (High Pressure Aeroponics)

Thanks for the responses guys. Unfortunately my last large
writeup in reply somehow was deleted after it posted...

@Grizz: The only problem is that for aeroponics to work correctly I need a fine mist that doesn't lead to water droplets building up on roots. That basically means about 1-5 seconds on time, 3-5 minutes off time. So the DIY probably wont work.

@CR: Good advice on the backups. I will try and purchase as many as possible but of course I am not made of money, in fact I don't have very much at all lol but a guy needs a hobby to keep him sane through pre-medical and medical school.

Would a 1/4'' fuel inline filter be OK to use in an aero system you think? Also, where could I find the right type of pressure release valve for this system? Would prefer not to have the accumulator turn into a bomb so I am looking for a releif valve but they are all crazy. Most of them are brass and have huge inlets.


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RE: HPA (High Pressure Aeroponics)

The filters are typically the common stainless steel mesh cylinders in a plastic housing. It's a similar filter used for a lot of different things, like drip irrigation or farm sprayers.

I think the easiest way to make a pressure release valve is to simply plumb a ball valve into your pressurized spray line inside the rail. You want that valve with a lot of pumps, like the shallow well pumps, because they are made to kick off when the pressure gets too high. All you have to do is leave the ball valve just a little bit open.

Here is a link that might be useful: a common filter design


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RE: HPA (High Pressure Aeroponics)

So would this AEM injection filter work? Says 40 microns and since it is mesh, should be easy to clean and use for a long time you would think.

Pretty stoked to get this system together. Waiting for some holiday gifts to arrive so sometime around the start of 2013 I should have the system up and running!!! Getting everything together now so I just have to worry about unexpected problems later on.

This project gets more and more expensive everyday, but it should be worth it. Hardly ANYONE uses the true aeroponic method with high pressure pumps and fine mists. Being able to own one of these systems is like owning a piece of fine art almost...

Can't wait!

BTW, CR, you are pretty familiar with high pressure aero. Do you happen to have a system yourself?

-mike

Here is a link that might be useful: AEM Injector Filter


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RE: HPA (High Pressure Aeroponics)

I think most filters like that would be fine. There shouldn't be anything in your system for it to catch, anyway.

I have played around with HPA before, enough to at least be able to build a poor man's version of it. I would love to build one for commercial growing of greenhouse tomatoes. But I think I would have to bury the misting chamber underground, because the hot sun heats the roots too much otherwise, and that effect is magnified when growing inside a plastic hoophouse.

I am building my first commercial greenhouse system right now, and it's mini-lettuce in a recirculating deep water culture, because of the hot roots issue. The mass of the water keeps it from heating up so fast in the hot sun. Plus, it's cheap, and I think I can re-coup my initial investment within 3-4 months. If it were a HPA system, it might work twice as well, but it would cost 4-5 times as much. Eventually, it would be profitable, but it would take longer to get there.


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RE: HPA (High Pressure Aeroponics)

Unfortunate about the heat issues. Aeroponics is such a ridiculous investment. But I will say, sourcing almost all of my parts from eBay, I will end up spending $300-350 for a 12 plant system. Not too shabby, although it would be much harder to justify if for profit instead of hobby.

On the matter of commercial aeroponics, I saw a link to a company selling what they call the "aerofarm." Check out the link if you want. It is ridiculous - LED lighting, CO2 regulators, high pressure aeroponics, multiple levels.

From what I saw they were wanting like $50K for the system?? Way too expensive to be profitable I would think, but who knows.

Here is a link that might be useful: Aerofarm


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RE: HPA (High Pressure Aeroponics)

Ethno wrote:

"@Grizz: The only problem is that for aeroponics to work correctly I need a fine mist that doesn't lead to water droplets building up on roots. That basically means about 1-5 seconds on time, 3-5 minutes off time. So the DIY probably wont work."

You should really contact hex about this matter. he is the one who gave me that timer diagram. I believe, it was something like 0.5 seconds on every 30 seconds. Also, by changing the resistors and capacitors, you can adjust the on and off times. Also, he presented the idea of a manual diaphram pump to charge an accumulator. The pumps are a lot less expensive and you only need to charge accumulators every couple of days. if you wanted to expand the system, you could just use one pump and move it to multiple accumulators.


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RE: HPA (High Pressure Aeroponics)

"if you wanted to expand the system, you could just use one pump and move it to multiple accumulators. "

Interesting, that's a hell of a concept.

Sorry, the link you referenced brought me to a page that stated this in the first line of text:

" A 1 minute on/4 minute off cycle timer you can make yourself for about $4."

Naturally I decided not to look any further since I need control down to 1 second intervals.

Maybe I just needed to look into it further. Sorry bout that Grizz

Hope Thanksgiving went well.


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RE: HPA (High Pressure Aeroponics)

  • Posted by nil13 z21 Mt. Washington L (My Page) on
    Mon, Nov 26, 12 at 19:29

That DIY timer is just a 555 chip. With the proper combination of resistors and capacitors you can make the interval pretty much whatever you want. Here is a basic primer. 555 timer


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RE: HPA (High Pressure Aeroponics)

For what it's worth I have had HORRIBLE luck with cycling a pump. I bought a pond pump and built a timer to turn it on every 15 minutes for 5 minutes. It worked perfectly for a few weeks. Then it started making vibration noise. ok, I can live with that. Then it stopped while I was at work. by the time I got home my plants were VERY wilted, I almost lost them all. That first pump lasted 3 months. I went to a local hydro shop and they sold me a high pressure pump for 80 bucks. It did the same, although it lasted 6 months instead of 3. I took it apart and noticed the plastic bushing worn in 2 places that corresponded to the poles of the internal magnet. When the bushing gets worn enough the pump would just bind at startup and hummmm away, but wouldn't push water. I figured that the pressure of starting the water moving from a standstill was what caused the bushing to wear. I bought a cheap pond pump, took out the timer and started running the pump continuously.
2 yrs later the pump is still working.
The only reason I was cycling the water was to cut down on electricity usage. But the cost of the ruined pumps was WAAAAY more than any electricity charges.
I have kept looking for a pump with metal bushings, but haven't found any.
p.s. all of the pumps were mag drive pumps.


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RE: HPA (High Pressure Aeroponics)

I plan on using a reverse osmosis "booster" pump. It is built for putting out high pressure.

To fix the constant on/off cycles that wears the pump out quickly, what I plan to do is add an accumulator.

Its just a large, pressurized metal tank that can be filled at one time with the pump. With an accumulator you no longer have to worry about the pump constantly cycling because all it has to do is fill the accumulator tank once every day or longer, depending on how big of an accumulator you get.

The other reason an accumulator is important is because they allow for a "constant" pressure to be applied to the water when the cycler timer turns on and opens the solenoid. This provides an instant mist with desired pressure nearly immediately.

Down side is that an accumulator costs about $50, some can be less, some more, and you need to add a pressure relief valve to the system to make sure the pump doesn't malfunction and continue pressurizing the accumulator till it becomes a literal bomb.


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RE: HPA (High Pressure Aeroponics)

I don't want to rain on your parade, but high-pressure systems are noisy, they are way more energy-intensive than other systems and they are extremely maintenance intensive. System components are way more expensive than low pressure systems. You will find that HP system components are also made of unobtanium.

High pressure systems will do nothing that a low pressure system will not do.

For the above reasons, high pressure systems are the exception that tests the rule.


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RE: HPA (High Pressure Aeroponics)

High pressure makes a small droplet size of mist that low pressure systems cannot. That's the difference, and that's why it works better.

http://en.wikipedia.org/wiki/Aeroponics
NASA has funded research and development of new advanced materials to improve aeroponic reliability and maintenance reduction. It also has determined that high pressure hydro-atomized mist of 5-50 micrometres micro-droplets is necessary for long-term aeroponic growing.

For long-term growing, the mist system must have significant pressure to force the mist into the dense root system(s). Repeatability is the key to aeroponics and includes the hydro-atomized droplet size.


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RE: HPA (High Pressure Aeroponics)

^^ exactly.

"high-pressure systems are noisy"

The pump I will use is a RO booster pump. I did the liberty of looking up some youtube videos of the pump running and its near whisper quiet. With the accumulator it will only be working for short periods of time anyways. Possibly once a day.

"they are way more energy-intensive"

mmmm, I cannot imagine much more energy intensive. Running the pump once a day to charge a pre-pressurized accumulator tank would actually save electricity. Remember, although this will not be the same setup to the "t", the HPA system was originally developed by NASA in order to conserve resources. I imagine running the pump so little will actually be very efficient energy wise.

"extremely maintenance intensive"

This I can agree with but if you have backups then its not a big issue. With the accumulator my pump should last years and under warranty. I purchased an inline filter with 200 mesh, so no debris should make it to the nozzles. Salt buildup on the nozzles will happen but I plan to make it easy to pull out the nozzles when needed. The ones I am getting can unscrew and be cleaned.

"more expensive than low pressure systems"

This is a definite. HPA is not for the family man that is tight on money but it is feasible for most people if you can be patient and save up parts over time till you can get the system together.

Despite the high cost and complexity of the system due to its high pressure requirements and frequent maintenance requirements, I am still pretty stoked to give it a go. I like building things and the satisfaction of even getting the thing together and working will be worth it. To grow plants with it... priceless.

This post was edited by ethnobotany on Sun, Dec 9, 12 at 2:06


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RE: HPA (High Pressure Aeroponics)

Wikipedia is unvetted crap.


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RE: HPA (High Pressure Aeroponics)

  • Posted by nil13 z21 Mt. Washington L (My Page) on
    Sun, Dec 9, 12 at 11:55

I don't think the pump is the main source of the noise, but instead it's the water being forcefully ejected from the nozzle that is noisy.

I was also under the impression that NASA uses aeroponics because the system is simpler to design, use, and contain in a zero gravity environment. Ebb and flow isn't going to work without gravity. HPA may be the most energy efficient system in a zero gravity environment, that doesn't necessarily mean it is the most efficient on Earth.


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RE: HPA (High Pressure Aeroponics)

''I don't think the pump is the main source of the noise, but instead it's the water being forcefully ejected from the nozzle that is noisy."

OK, so let me get this straight. Those sprayheads in the fruit/veggie section of your local grocer are loud and noisy? They are pretty quiet if you ask me.

"HPA may be the most energy efficient system in a zero gravity environment, that doesn't necessarily mean it is the most efficient on Earth."

No, you're right. That I can agree with, because you cannot generalize the results of an experiment done in zero gravity against those on Earth. On the same token, I know for a fact that a continually running pump in say a low pressure aero system or NFT system will use more electricity than a high pressure pump running a very short period of time everyday. Sure there is the electricity to run the solenoid, too, but that will likely be negligible compared to pump electricity use.

In my opinion its simple logic.

The pump for an NFT or low pressure aero system must provide more volume of water and for longer periods of time than a high pressure system. Not only that, but my little RO booster pump is more energy efficient than a magdrive pump. Check it...

Ex. This 500 gph Magdrive pump needed for LPA or NFT uses 45 watts

http://www.marinedepot.com/Danner_Mag_Drive_Supreme_5_500_GPH_Water_Pump_500_to_1000_Gallons_Per_Hour_Submersible_Aquarium_Pumps-Danner_Mfg.-DN1119-FIWPSBFT-DN1123-vi.html

This aquatec 8800 RO booster pump uses 24 watts:

http://www.aquacave.com/AQUATECH-8800-RO-Booster-pump-Assembly-P1816.aspx


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RE: HPA (High Pressure Aeroponics)

A high pressure pump takes scads of kw to start and run, even for a short time. There's no reason to run a low pressure pump all the time any more than you have to run a HP pump all the time.

HP pumps will use more electricity than LP pumps.


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RE: HPA (High Pressure Aeroponics)

"A high pressure pump takes scads of kw to start and run, even for a short time"

You sir have no proof whatsoever of this claim. I have no reason to believe that a little 12 V, 24 watt pump uses anywhere near 1 kw to start up. You just aren't reading my material if you think my RO pump uses that much electricity. Maybe a well pump or something of that sort, but not a RO pump.

For NFT you will use the magdrive pump continuously. For LPA, the pump could theoretically be ran the same amount of time as HPA (most people run them much longer than HPA, however). I reference you to my previous post that shows a 500 gph magdrive pump will use 2x the watts to run as my RO booster pump for the same amount of time.

Unless you show factual proof that starting an aquatec 8800 RO booster pump uses more electricity than starting up a decent size magdrive pump, then you cannot correctly make any claim that HPA uses more electricity. Plain and simple.

-Mike


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RE: HPA (High Pressure Aeroponics)

You need to learn something about the physics of fluids and electric motors.

High pressure= high HP


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RE: HPA (High Pressure Aeroponics)

Obviously you have no idea what horsepower means?

"Horsepower (hp) is the name of several units of measurement of power, the rate at which work is done. The most common conversion factor, especially for electrical power, is 1 hp = 746 watts."

Horsepower can be directly converted to watts.

AGAIN,

my RO pump uses 24 watts. The magdrive pump I listed uses 45 watts.

Get the picture ?


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RE: HPA (High Pressure Aeroponics)

You know, I wish we had moderators to kick trollers out the hydro forum.

Ridiculous.

Please, can we limit further posts to constructive criticism or advice rather than just putting the system down?


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RE: HPA (High Pressure Aeroponics)

So I received most of the items for the system. Waiting on a few odds and ends to come in the mail before it is setup. Here are the items I have so far:

IMG_2360_zps7a619032-1_zps3f27d05d

We got a 2 Gallon well-x-trol accumulator tank, pressure switch, pressure gauge, Aquatec 8800, 24 V to 120 V transformer, ART DNe Recycle Timer, and 1/4'' food grade RO tubing.

Now I just need my john guest tees/elbows, the pressure relief valve, solenoid, and the 200 mesh filter. All of which are conveniently coming from the same company and should be here Mon-Wed sometime.


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RE: HPA (High Pressure Aeroponics)

Ethnobotany;

I am very interested in the HPA system you designed. I am new to this and would like to duplicate your ideas. Is it up and running now?? If possible please post an updated photo of all the system's components. Please update the systems current status. Your system seems to solve a problem I have with the current configs I have seen. Could you please update your profile so that I may communicate with you through the site? Thanks!


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RE: HPA (High Pressure Aeroponics)

Hey there! Excellent, I was hoping someone else would want to try out this system too : )

Zoomed out view of the system

 photo 6a399d1e-bcab-4e91-b38e-22a895956306_zpscb7f065d.jpg

Sprayhead

 photo 207139e1-42db-489e-a4f3-63280b861780_zps17ed5d2d.jpg

Two filters, left one is between pump and the rez, the right filter is between the solenoid and misters

 photo 7b4321dd-7335-42f3-b373-3698ed54831c_zps8f98b2b5.jpg

Here is a shot of the components neatly arranged in the container. On the left you see the pump, followed by the pressure switch. Center you see the pressure gauge, then right of that you can sort-of see the solenoid. Lastly, in the distance is the accumulator with pressure relief valve.

 photo IMG_2465_zps80d057c1.jpg

I actually had to scrap the previous plants in this system because after 2 months, a nutrient film apparently formed on the rubber bladder in the accumulator. This lead to tiny pieces of film clogging the sprayheads, even after cleaning them repeatedly. My plants unfortunately died after 3 days of no water and me not figuring out what was going on.

Since then I have done a system clean out with bleach, and I added the second filter shown in the previous picture to prevent any salts/nutrient film in the accumulator from reaching the sprayheads. Problem has been solved and lesson learned - two filters are necessary if you use an accumulator.

 photo ac9eb912-9081-4fa3-a9ec-f55a48ffd469_zpse355c979.jpg

My next crop is going to be Ozark Beauty strawberries

This post was edited by ethnobotany on Fri, Mar 22, 13 at 1:06


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RE: HPA (High Pressure Aeroponics)

Learnt a lot from following your setup.
Does the problem with the nutrient film in the acumulator mean you have to periodically clean out the accumulator?

In hindsight, would a different type of accumulator prevented this problem?


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RE: HPA (High Pressure Aeroponics)

No, I don't think a different accumulator would do anything. I recommend having a filter between the accumulator and the sprayheads to fix this problem, and then in between crops flush the system out and let it run with bleach water for a day or two just to get rid of anything in the accumulator.


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RE: HPA (High Pressure Aeroponics)

Nice work, ethno
Personally, i`d use the totes for the roots and repurpose the cramped troughs for nft lettuce or basil ;)
I`ve never had an issue with biofilm buildup in the accumulators or anywhere else in the system. I add a touch of bleach (2-5ppm) to the nutes, prefilter down to 1 micron (overkill) before the accumulator and run *drain to waste.
*collected and used on the soil garden.
Something i would recommend is a pressure regulator, it will ensure your nozzle flowrate remains constant. Without a regulator you`ll get progressively lower flowrates as the pressure in the accumulator drops from max to min.


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RE: HPA (High Pressure Aeroponics)

Nice tips hex. Got any pictures of your setup? I bet the reason you don't get the biofilm is due to the drain to waste, as you pointed out.

What kind of nutrient strength do you use?


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RE: HPA (High Pressure Aeroponics)

Depends on the plant/stage of growth but for toms in full fruit its never above 1.0 EC.
Drain to waste is clean and easy, you dont have to worry about imbalances, ph shifts or nasties taking up residence in the res as nothing comes back. I rarely bother to check the ph or ec these days unless i`m testing a new nute recipe. I use homebrew nutes and ro water for repeatability..

I can`t understand why aero has the rep of being high maintenance, its a breeze compared to nft.


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RE: HPA (High Pressure Aeroponics)

Hex,
If you used a deeper container (a rubber tote) for the plants, would you have to set the misters farther down from the top of the tote and/or space them farther apart?


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RE: HPA (High Pressure Aeroponics)

Hi Grizz
Depends on the spray pattern and throw of the nozzles but generally you`d locate them towards the top of the chamber firing between and below the netpots. Aim to get an even coverage at the top and let gravity do the rest. .

My outdoor chamber takes 3 gallons of nutes a day running drain to waste. If the 20w solar charger packs up, i`ll have 29 days until the 12v 7AH battery runs flat..

 photo 2011tomato.jpg

This post was edited by hex2006 on Fri, Mar 22, 13 at 19:49


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RE: HPA (High Pressure Aeroponics)

Can I get a few different opinions on drain to waste? What are the benefits? Do they really outweigh the cost of using more nutrients?


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RE: HPA (High Pressure Aeroponics)

Drain to waste is only practical with a few hydro methods, HPA is one.
The main benefit is the control you gain over the nutes.
The plants always have the full range of elements in the correct balance. Deficiencies are unlikely to occur, unless something was already missing or out of balance when you mixed up the nutes.

DTW requires less maintenance, the EC and pH are more stable and in most cases its easier to control the nute temperature.
High nute temps can lead to root rot issues, if it gets into a recirculating res it can spread through the system .

Weighing up the pro`s and cons, the nute cost is minimal. I think Grizz uses agricultural hydro nutes, might be worth asking him for the suppliers phone number.


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RE: HPA (High Pressure Aeroponics)

Some HPA setups use big pumps like a well pump; they move too much fluid to run drain to waste.

It would be neat to be able to run two different misting cycles if you had drain to waste. At night, you would need fewer cycles, and increasing the interval between them would save nutrients. I have never seen a cycle timer that would do that, though.


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RE: HPA (High Pressure Aeroponics)

Aero is all about control.The hardware just provides the means.
.A well pump could work with an acccumulator and solenoid to provide the control. A small ro booster pump with an accumulator is more than capable plus Its cheaper,quieter and uses less power.

Its hard to find a versatile cycle timer at the right price. I`ve always made my own which are cheap and reliable but a bit limited on features..
So I devised a pc controlled hardware/software cycle timer. It can control 4 seperate systems and change the cycle timing upto 4 times a day based on what time it is.
i used it last year to run the outdoor chamber, a hp aero cloner and the pump on a flood and drain tray.

 photo pcmulticycletimer.jpg

This post was edited by hex2006 on Sat, Mar 23, 13 at 22:02


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RE: HPA (High Pressure Aeroponics)

Ethno & Hex;

Great ideas and great systems! After much thought, I believe I need a hybrid system for my needs that would require elements of both a HPA and a LPA system. I invite input from those who have experience with both HPA and low pressure misting solution. The plants i will grow under mist are terrarium varieties that I will apply fertilization to the mist. Both moisture and nutrients will be absorbed by leaves and roots growing on a solid substrate under a mini-greenhouse. Because the zone will be fairly large (3' x 24') I will have no choice but to recirculate misted water. That's why elements of the HPA setups appear more attractive. However, I do not think I need the ultra-fine spray.

What I plan to get:

a. DIG-5006 IP Timer
b. DRAMM STIX sprayers
c. MISTSOL Misting Solenoid Valve ( 2)
d. Ethno's RO Pump and a submersed pump.
e. A LARGE Accumulator
f. Pressure Gauge
g. Full-House RO Water Filter
h. Filter to pump.
i. Filter from Accumulator.

I like Ethno's 24 W pump and accumulator combination. Because my area is large, I will use low-pressure sprayers, Ethno's RO Pump and the largest accumulator that is realistic for me to use with the area I plan to cover.

In order to deal with the inevitable nutrient inconsistency that develops as plants grow, I will use a Conductivity and TDS Controller to control a small pump to pump 1/2 the reservoir out when the conductivity fluctuates outside acceptable levels. A float-valve will then refill the main reservoir from a separate pre-mixed nutrient reservoir. I need the system to be as low-maintenance as possible.

I am hoping with your practical experience, you guys may point out weakness in the system and suggest corrections.

~Thanks!

This post was edited by Boukmn on Mon, Apr 1, 13 at 7:46


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RE: HPA (High Pressure Aeroponics)

Well pumps don't need accumulators. That's the point of using the well pump. They are big, loud power hogs, but they work great if you have a large area to mist.


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RE: HPA (High Pressure Aeroponics)

Hex
Did you code the pc timer yourself or did you buy it / is it shareware?
In either case, what driver do you use to communicate to the solenoid. I assume you're sending a signal out a pc port to flip a relay to engage the solenoid, but how do you tell the computer to send a signal? It is something I've been digging around to try and do for some time now but have never found a working solution. If you could point me in the right direction, I would appreciate it.


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RE: HPA (High Pressure Aeroponics)

Hi Grizz
I bought a commercial usb automation board which takes care of the comms via a DLL. The board has logic level outputs so i added a ULN chip (darlington transistor array) which can drive upto eight 12v relays directly.
I had to relearn how to code as the last time i did any was way back in the early 80`s on a zx spectrum. A professional programmer would have done a much better job in half the time but as long as it works i`m happy.
I have a lux meter with a logic level output i`d like to incorporate so the mist frequency is geared to the light intensity. It`ll have to wait until my programming skills improve but could be a good feature for my outdoor setup where passing clouds can block out the sun.

This post was edited by hex2006 on Mon, Apr 1, 13 at 22:30


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RE: HPA (High Pressure Aeroponics)

Hi Boukmn
If you are misting above the plants it would be pretty easy to cover a 24ft x 3ft area. High pressure aero performs like low pressure aero if you increase the misting frequency. The main difference is you`ll get a more even coverage and use less water.

A well pump wont do much if you turn it on for one second ;) You could run a 24` x 3` chamber on an tiny aquatec 6800 with an accumulator. I wouldnt recommend it but it can be done.


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RE: HPA (High Pressure Aeroponics)

Yeah, a well pump would take 3-5 seconds to get pressure. Something like 30 seconds on and 5 minutes off works fine.


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RE: HPA (High Pressure Aeroponics)

30 seconds will completely soak the roots and the result will be no different to low pressure aero. If you run a bucketful of water to the roots at low or high pressure, its still a bucketful of water ;)


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RE: HPA (High Pressure Aeroponics)

I stumbled across this thread conducting some research. I read through it and found there to be quite a bit of misinformation so I decided to create an account and clear some things up.

We are working with HPA and are developing an affordable commercial scale system. Our system can also be used with LPA and AAA.

First, HP pumps are not expensive to operate, noisy yes, expensive to operate, no. We logged only 0.02 Kwh per day with two of our 100 PSI on demand pumps. That's less than $1 a month to operate.

Also, you do not need a large accumulator. We use a 24oz accumulator to operate 22-23 (.18 Lit/Min @ Bar 6) nozzles. The purpose of an accumulator isn't to "store" liquid, but to provide smooth operation for the pump in order to increase life. Large accumulators are used for expansion in plumbing systems, so if you are using a large accumulator you are simply taking up space you don't need to.

HPA will outperform LPA all day long. In an HPA environment, plants grow multi-cell root hairs. These fine root hairs will never be established in LPA. Truth is, LPA is nothing more than a hybrid of NFT/Flood and Drain on a timer.

Plant roots that develop multi-cell root hairs can absorb more nutrient than roots that do not have them. Also, the root mass does not grow as large in HPA ans LPA.

The two main advantages to HPA are about 20% faster growth due to multi-cell roots and water usage. Our system uses 3.4 gallons, per plant site every 45 days. The typical recirculating LPA system will use 6 gallons or more. HPA can be operated drain to waste, LPA can not, at least not efficiently.

We currently run 3 seconds on, 3 minutes off. You can check out our video at:

Here is a link that might be useful: Root Hair Video

This post was edited by ccsykes on Tue, Apr 2, 13 at 20:17


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RE: HPA (High Pressure Aeroponics)

Re: 30 seconds will completely soak the roots and the result will be no different to low pressure aero. If you run a bucketful of water to the roots at low or high pressure, its still a bucketful of water ;)

Sorry, but it doesn't work that way. At high pressure, the mist is atomized. The run time of the pump doesn't change that. Even if the pump never shut off, it would still outperform LPA. The only reason to shut the pump off at all when using a well pump is that it will heat the reservoir water if run continuously.


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RE: HPA (High Pressure Aeroponics)

The quantity of water atomised by the well pump will be based on its flow. If it atomises a gallon of water every 30 seconds, thats the quantity you`ll deliver to the roots. With 1 second its 30x less. HPA isnt just about the mist quality, the quantity is equally important. If the roots are kept too wet, you wont get root hair growth.


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RE: HPA (High Pressure Aeroponics)

"Large accumulators are used for expansion in plumbing systems, so if you are using a large accumulator you are simply taking up space you don't need to."

Your pump(s) could be running upto 80 times a day. A large accumulator will run a large setup for several days . As an example, the hpa chamber in the pic earlier in the thread has 32 sqft of planting area and a volume of 56 cubic feet.
The accumulator allows it to run at a constant 90psi for several days. Its completely offgrid and uses no mains electrical power.

Accumulators are immune to power outages once charged and there are no moving parts to break.


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RE: HPA (High Pressure Aeroponics)

If the roots are kept too wet, you wont get root hair growth.
What no one realizes about HPA is that by the time you get an established plant, most of the root growth is from the NFT effect of the misted water running through the chamber back to the reservoir, rather than the actual mist itself. That's why HPA has such a big advantage for cuttings and seedlings - they don't have enough roots yet to take advantage of the flowing water. But for very big plants, aeroponics can even be a disadvantage, because the mist does not penetrate to the center of the root ball and it will start to rot inside.


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RE: HPA (High Pressure Aeroponics)

I use a little over 3 teaspoons of nutes per misting in a 56 cubic foot chamber. The daily run off may be enough to fill a glass or two but its by no means an nft flow. I ran an 11ft outdoor nft bed with toms last year in a sunnier part of the garden. The hpa had faster growth rates in all stages and was much lower maintenance.
 photo outdoornft.jpg

No nft for me this year but i may be running an AA aero setup outdoors just to see how it copes in full sun and how it compares with the hpa.

Do you have any pics of your hpa setup?


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RE: HPA (High Pressure Aeroponics)

"Your pump(s) could be running up to 80 times a day. A large accumulator will run a large setup for several days . As an example, the hpa chamber in the pic earlier in the thread has 32 sqft of planting area and a volume of 56 cubic feet."

Volume and pressure are two different things. It doesn't matter how large an accumulator is, pressure will drop based on the volume expelled. So either my pump runs 80 times a day for 2-4 seconds each, or yours runs for 3-5 minutes to move the same volume. In either case, we both push the same volume to the pressure desired. In a diaphragm pump, it is the diaphragm itself that typical wears out. The motors will last a long time regardless of whether they are short cycled, or long cycled.

"The accumulator allows it to run at a constant 90psi for several days. Its completely offgrid and uses no mains electrical power. Accumulators are immune to power outages once charged and there are no moving parts to break. "

I'd be real interested to know how many nozzles and what flow rates you are using. We have determined at least 45- 60, 120 degree .18 Lit/Min @ Bar 7 nozzles are needed to effectively fog 32 cubic feet in short bursts. Even a large accumulator would begin to loose pressure relatively quickly with that much volume. We get about 102-112 plant sites per 32 s/f.

This post was edited by ccsykes on Wed, Apr 3, 13 at 21:26


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RE: HPA (High Pressure Aeroponics)

Nice plants! How hot did it get outside during the day? And how did you like your tomatoes, quality-wise?

When I say 'nft effect' that is my own unusual phrasing. But think of each root, as the mist condenses and runs down it, the water will create a thin film over the root. Technically, at the root surface, that should be bad, because it is a lower oxygen percentage. But because the film of water is rapidly moving downward, it is turning over new surface area and stays highly aerated. If maintaining the highest possible oxygen/water percentage in the air of a root chamber was the most important goal, then ultrasonic foggers should show a big advantage over HPA, and I don't think they do at all.


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RE: HPA (High Pressure Aeroponics)

"When I say 'nft effect' that is my own unusual phrasing. But think of each root, as the mist condenses and runs down it, the water will create a thin film over the root."

If the mist is atomized properly, there is no condensing. The water mist simply clings to the mutil-cell root hairs. What doesn't cling, floats down.


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RE: HPA (High Pressure Aeroponics)

The problem, I read, with ultrasonic foggers is keeping the mist contained inside the system. Apparently if you don't keep them pretty much "air tight" you lose a lot of nutrient to evaporation/dissipation.
@ CC,
While I am inexperienced at HPA, 60 misters to cover an 8' x 4' area seems excessive. That is something like a 6" x 12" spacing.
I thought something more along the lines of 24" x 24" spacing was what was required. Where do you get your spacing calculations from?


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RE: HPA (High Pressure Aeroponics)

Just wanna say this is an awesome discussion guys. Carry on!


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RE: HPA (High Pressure Aeroponics)

I use 12 long throw, narrow cone nozzles mounted high in the chamber. The overlapping mist from the nozzles fills the top of the chamber and gravity does the rest.
If they were upward facing i`d have less coverage per nozzle and water dripping from the underside of the lid.
Thats not to say it wouldnt work for a chamber of a different size, shape or planting layout.


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RE: HPA (High Pressure Aeroponics)

"I thought something more along the lines of 24" x 24" spacing was what was required. Where do you get your spacing calculations from?"

No calculations, simply from trial and error. For example, in the video below, we are using 45 nozzles. You will notice some of the outer plants are smaller than the plants close towards the middle. We determined that we need to add additional nozzles along the outer edge.

We've grown Basil and lettuce so far. As for the roots, they tend to grow out horizontal with upward nozzle placement. When we experimented with nozzles spraying down, the root mass tended to grow down and fill up the bottom of the tray.

Here is a link that might be useful: 22 Day lettuce test grow time lapse.


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RE: HPA (High Pressure Aeroponics)

Nice video sykes. If you had put the days on the video (or on a placard on the table) it would have been easier to tell where in the grow cycle you were.
Was the 24/0 light cycle at the beginning or end of the grow?
Is the table in the video an 8'x4' table?
You don't have pictures of the inside do you?


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RE: HPA (High Pressure Aeroponics)

Here's the inside.


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RE: HPA (High Pressure Aeroponics)

I want to truly thank you ethnobotany for this fabulous post I was pondering down this path of true HPA and had just located the inline dc booster pumps but it was in boating same type of pump but using your post and finding everything I needed in an RO system and not only that all the support items tubing and great pictures. You have more than made my day . I have one question what is your schedule for charging the Accumulator for nutrients, do you flush at all or just recharge when needed.


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RE: HPA (High Pressure Aeroponics)

When I made this thread it was partly to help compile my own parts list but also to help other people have a good reference to make their own HPA too, so I am very glad to help and it seems like my goal is slowly coming to fruition : )

Right now my accumulator charges whenever the psi drops to 60 psi, and the pump stops filling it when it reaches 80 psi. My accumulator currently refills every ~1.5 hours or so (2 gallon). So it recharges as needed I suppose. Its all automated.


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RE: HPA (High Pressure Aeroponics)

Hi again: 1st of all I want to thank you for your fast response to my last post. I was going over your posts again getting last minute questions out of my system and I ran across your post about Drain to waste or not. I got some real good information from a guy named Pete Floria that I've been reading on. He's been at this HPA for few years now and like you he does a very good job relating out his experiences and gives some very good information this is a link to one of his posts and about 1/2 down is about Drain to waste or not https://www.icmag.com/modules/Journal/viewentry.php?journalid=328&goto=newcomment

This is an excerpt from that post:

Recycle vs Drain to Waste (D2W)

Recycling nutes back to the rez is a BAD IDEA!

Testing ppm/pH of my run-off/waste in mid-bloom, pH is 3-5 points higher (5.9 in my rez- 6.4 waste); and ppms are off the chart- 850 in the rez- 2000+ in the waste. That is toxic! Plus many of the nutes have been taken up by the plant, the left overs are out of balance. This is why DWC typically runs into nute deficiencies, and lock out caused by the imbalanced NPK ratios

One of the many benefits of TAG/HPA is how little nutes are needed. This allows you to D2W in good conscience. I dump the rest in my garden, lawn...

Now to my questions:
What value, trip pressure, and where did you get your accumulation tank pressure relief valve?
The 2 filter assemblies you use between res tank and mister where did you get them ?
At what PSI is your system running by your meter?
Do you use a pump to deliver from res tank to to the aquatic 6800 ? If yes what gph is it?
I noticed the bubble wrap around the accumulator tank is this for noise or temperature ?
What is the size of the tubing coming from the booster pump out to pressure switch?
Finally (I'm sorry) could you breake down the types of hardware from the accumulator tank out ie type of T, and connectors on both ends of T?


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RE: HPA (High Pressure Aeroponics)

My pressure relief valve is spring-loaded and opens at 125 psi. I got the accumulator from either amazon or eBay for ~$40-50. You could probably get a similar one at Home Depot/Lowes, I saw some there for nearly the same price while browsing the other day.

I bought a few things on eBay before I realized that if I bought most of my items from the same place (T's, tubing, relief valve, filters, etc.) then I would save money on shipping costs. This brought me to:

https://www.freshwatersystems.com/

I bought my pressure relief valve, tubing, john guest T's, and 200 mesh filters through them. They have tons of adapters and other quick connect 1/4'' or 3/8'' pieces so you can customize your system pretty easily if you want.

The bubble wrap surrounding the accumulator is for noise and it helps keep the tank stationary.

My pump connectors are 3/8'' (they offer 1/4'', but I failed to notice that the one I ordered was 3/8'') so the tubing you see is initially 3/8'' and then after the pressure switch I used an adapter to switch over to 1/4''.

The accumulator tank has a 3/4'' threaded hole (either that or 1/2'', can't remember) at the bottom (male I believe) and so I used a 3/4'' PVC threaded tee (3 female) to connect to the tank and used plumbers tape to make water tight. Used plumbers tape on the relief valve and screwed that into the T. Then I used a 3/4'' to 1/4'' quick connect threaded male adapter. to connect 1/4'' tubing to the tank.

DtW is something I would consider if I had more room to collect the waste, and especially if I had a single chamber with only a few sprayheads as opposed to 16 sprayheads in 4 gullies. In other words, my 16 sprayheads produce more daily run-off than I would like so until I get some sort of under-bed tote or dish out the money for a EnF Tray with lid then I am going to continue to use a recirculating system.


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RE: HPA (High Pressure Aeroponics)

Ethno;

I am finding it difficult to identify with certainty some of the parts you used for your system when I seek them out for purchase For example; you listed:

"PRESSURE GAUGE

SOLENOID VALVE W/ 1/4'' QUICK CONNECTORS

PRESSURE SWITCH
- this is factory set to turn the pump on when pressure falls below 40 psi, and to turn off when the pressure rises above 55 psi.
- it can be adjusted +/- 5 psi for both values

FOGGER MISTERS
- these have a 0.8 GPH rating
- 35 to 80 psi rating
- droplet size of 60 to 100 micron
- cleanable "

What exactly is the make and model of these items and can you please post links to where they can be purchased? I am now realizing as a newbie, it is very easy to make mistakes purchasing similar (read: wrong) items. _ thanks!

This post was edited by Boukmn on Sun, Apr 14, 13 at 15:10


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RE: HPA (High Pressure Aeroponics)

Hi Boukmn: I am also building this system and and am a newbe at this also this is what I found out from Ethno and my trial and errors hope it helps.
Almost all items are available on e-bay search under RO systems and there is a aquatic 6800 pump kit that has all the parts pressure gauge, switch & pump in it for $108.00.

Search the perimeters of your misters at e-bay search and you"ll get the exact mister beware they have threaded and barbed 10 for $12.99.

Ethno also guided me to this company and I saved a lot on the John Guest connectors http://www.freshwatersystems.com this is also the only place I could find the 1/4" filters Ethno used.

One other thing I stumbled across in this process was the use of a regulator in this system to assure no drop of PSI @ misters between pumping' s / charging of the accumulator this will cause spurting of misters and droplet size "which is all critical" would vary. Search e-bay for Watts P60-m1-4 Pressure regulator it's adjustable from 0 to 125psi and is set up for 1/4" in outs $29.95.

The only other thing I had problems with was the system Ethno used at the input to the accumulator tank. He used a 3way threaded female 3/4" Tee and I could not find the John Guest reducer that he used to go from the 3/4" Tee to 1/4" tube. I ended up using a female Tee fipt x slip x slip and reduced the 3/4" slip to 1/2" male fipt then I could find a John guest connector to make the connection and hook up the 1/4" feed tube to the system.

Something else I found was to use a rubber stopper with 3/16" hole through it to mount your spry head to your system it allows you to feed your 1/4" tubing to your spray head through it and not only seals the hole that the spry head enters but you can adjust the spray head to what level you desire. This is a link I found to buy the stopper http://www.widgetco.com/2-rubber-stoppers-plugs-1-hole.

Hope this helps.


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RE: HPA (High Pressure Aeroponics)

Its better to run larger bore lines between the tank and solenoid to keep pressure loss to a minimum. Its important if you plan to run a lot of nozzles and/or long runs of 1/4" tubing.
The more nozzles you have, the higher the flow and the higher the loss. The larger bore lines will add a little extra capacity to your accumulator.


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RE: HPA (High Pressure Aeroponics)

Thanks hex2006: I was thinking about the larger line in that part of the system it's why I went for the regulator. I just love this site so much good info I noticed with Ethno's system that he used 3/8" line by error and was probably a good thing for when he ordered his pump kit he got the 3/8" system and reduced later on in his system to 1/4". I will be starting out with 6 misters on this system and plan to add another 6 for a total of 12 misters. It is a good thing I'm about 1 to 2 weeks from ordering all parts and can still make adjustments. Thanks again.


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RE: HPA (High Pressure Aeroponics)

I've been using hydroponics and lp aero for several years now. After reading up on hpa I've realized this is the holy grail of the ponics. I'm planning on setting up a vertical hpa DTW system in my greenhouse this month. I've purchased several of the components already including:
Acuatec DDP 5800 for psi 80-120
Transformer
Solenoid Valve
Pressure Switch
There are a few more things to gather over the next couple of weeks including a cycle timer and accumulator tank.
I am looking turn (3) 50 gallon drums into vertical grow chambers with around 90 sites each. I will have the reservoir under the table where the 3 drums sit. I'm planning on using the cycle timer for 3 sec on/3 min off. The water will run from the reservoir into each chamber. The bottom of the chambers will each have a drain that will connect to the other chambers and then exit. My main question right now is:
Is it possible to run 3 50 gallon drums at 100 psi off the pump I have? I was originally looking for the acuatec 8800 but was told by a tech that this pump is meant to run at higher psi. Also, how many nozzles should each chamber have on the inside? I am making a DIY of the "Art Garden" btw. Thanks guys!

This post was edited by hpanube on Sun, Nov 9, 14 at 23:50


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RE: HPA (High Pressure Aeroponics)

The roots would do best of you had something to support them inside the drum. Otherwise, they weigh themselves down and don't fill all the available space. The smaller crops like mini-lettuce would have the least problem. But bigger rootballs would like some support so they can fill all the space you want them to.

One of the things I've noticed is that as soon as your mister shuts off, and the solution runs back to the tank, for those few moments you actually have an nft system. The roots are feeding off the nutrient film that is running back to the tank. So I think the holy grail would be HPA coupled with the perfectly angled interior slope for the NFT effect to occur.


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RE: HPA (High Pressure Aeroponics)

Thanks Cole_Robbie: What do you think would be a good way to support? I'm almost thinking of a SCROG for the roots.. Like a cylindrical screen that rests in the drum. I'll be growing mainly lettuce for the first trial run. I'm hoping to dial in the mist to the point where there's minimal runoff, like ccsykes.


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